Weld-In Manifold Plug - Indmar Exhaust Port Freeze Plug

The Indmar Weld-In Manifold Plug is a durable metal plug designed to be welded into an exhaust manifold or similar engine manifold opening to permanently seal an unused port or repair a damaged port. Ideal for inboard marine engine service and custom manifold work, this weld-in plug provides a strong, leak-resistant seal once properly fitted and welded.

• Brand/Vendor: Indmar
• Product type: Weld-in manifold plug / port seal plug
• Application: Exhaust manifold or engine manifold port sealing (inboard marine engines)
• Install method: Weld-in (requires proper prep, fit-up, and welding)
• Material: Metal (weldable)

Why you’ll want it: When you need a permanent fix—rather than a temporary cap—this weld-in manifold plug helps prevent exhaust leaks, water intrusion, and loss of performance caused by open or compromised manifold ports.

FAQ

Is this a press-in/freeze plug?
It is designed to be welded in place for a permanent seal, not simply pressed in.

Will this fit my engine?
Fitment depends on your manifold port size and application. Measure the port opening and confirm compatibility before purchase.